lQ
Two independent charge-transfer (‘QT’) touch keys
Individual outputs per channel - active high
Projects prox fields through any dielectric
Sensitivity easily adjusted on a per-channel basis
100% autocal for life - no adjustments required
3.9V ~ 5.5V single supply operation
10s, 60s, infinite auto-recal timeout (strap options)
Sync pin for line sync to suppress noise
Spread spectrum operation
Pin options for auto recalibration timings
Extremely low cost per key
20-SSOP Pb-free package
SNS1A
SNS1K
n.c.
SPEED
n.c.
OUT1
OUT2
VSS
SYNC/SS
n.c.
1
2
3
4
QT220
5
20-SSOP
6
7
8
9
10
15
14
13
12
11
16
20
19
18
17
QT220
2 K
EY
QT
OUCH
™ S
ENSOR
IC
SNS2K/OPT1
SNS2A
OPT2
n.c.
n.c.
OSC
VDD
/RES
n.c.
n.c.
APPLICATIONS
PC Peripherals
Backlighted buttons
Appliance controls
Security systems
Access systems
Pointing devices
Instrument panels
Gaming machines
The QT220 charge-transfer (“QT’”) QTouch IC is a self-contained digital sensor IC capable of detecting near-proximity or touch
on 2 electrodes. It allows electrodes to project independent sense fields through any dielectric like glass, plastic, stone,
ceramic, and wood. It can also turn metal-bearing objects into intrinsic sensors, making them responsive to proximity or touch.
This capability coupled with its continuous self-calibration feature can lead to entirely new product concepts , adding high value
to product designs.
Each of the channels operate s independently of the other, and each can be tuned for a unique sensitivity level by simply
changing its sample capacitor value. Two speeds are supported, one of which consumes on ly 90µA of typical current at 4V.
Unique among capacitance sensors, the device incorporates spread spectrum modulation for unsurpassed EMC compliance.
The devices are designed specifically for human interfaces, like control panels, appliances, gaming devices, lighting controls,
or anywhere a mechanical switch or button may be found; they may also be used for some material sensing and control
applications.
These devices feature a SYNC pin which allows for synchronization with additional similar parts and/or to an external source to
suppress interference. This pin doubles as a drive pin for spread-spectrum modulation. Option pins are provided which allow
different timing and feature settings.
The RISC core of these devices use signal processing techniques pioneered by Quantum which are designed to survive
numerous real-world challenges, such as ‘stuck sensor’ conditions, component ageing, moisture films, and signal drift. By
using the charge transfer principle, these devices deliver a level of performance clearly superior to older technologies yet are
highly cost-effective.
AVAILABLE OPTIONS
T
A
-40 C to +85 C
0
0
SSOP-20
QT220-ISSG
LQ
Copyright © 2005 QRG Ltd
QT220R R1.02/0905
QUANTUM [ QUANTUM RESEARCH GROUP ]
